1. Field of the Invention
The present invention relates to a frequency division multiple access, and more particularly, to a method and apparatus for compensating for the frequency offset in an interleaved frequency division multiple access.
2. Description of the Related Art
The frequency offset in an interleaved frequency division multiple access (IFDMA) communication device decreases a signal-to-noise ratio (SNR) by changing the magnitude and phase of a signal that is transmitted from a transmitter to a receiver and creates interferences among users. IFDMA refers to a method of realizing multi-carriers in a time domain, which was disclosed in the paper of “Interleaved FDMA-A New Spread Spectrum Multiple Access Scheme”, by Uli Sorger, Isabellar de Broeck, and Michael Schnell 1998 in International Conference on communication (ICC) proceedings, 1998, pp. 1013-1017. Here, the frequency offset is caused by a difference between oscillation frequencies generated by a transmission oscillator of a transmitter of the IFDMA communication device and a reception oscillator of a receiver thereof. To solve this, i.e., to minimize the frequency offset, very sophisticated analog radio frequency (RF)/intermediate frequency (IF) components should be used in the transmitter and the receiver of the IFDMA communication device. However, it is difficult to realize analog RF/IF components satisfying desired performances as the frequency offset increases. Also, although the analog RF/IF components are realized, the manufacturing cost thereof is high.